July 24, 2022
8 min read

What are the world’s rarest diamonds?

What are the world’s rarest diamonds?
Frame 26

Diamonds are already considered rare and unique stones – a real miracle of nature. They are formed underground for thousands of years and exposed to various chemicals, gradually acquiring their beautiful and incomparable appearance.

Be that as it may, even among these unique stones themselves, there are those that are considered the rarest and therefore the most precious. 

The rarest diamonds by color

Fancy color diamonds coming in a wide range of colors – from blue to black – comprise only 0.01% of all diamonds mined worldwide. However, they can boast of such rare shades that many have not seen in their entire lives.

Red Diamonds

Here they are – the most expensive diamonds in the world! Their price and incredible value are related to their scarcity. Among all fancy color diamonds, they are found least often.

Known as Fancy Reds, they demonstrate a variety of color shades from orange-red to brownish red. Most Red Diamonds are mined in the Argyle Diamond Mine located in Austria. 

The Moussaieff Red diamond

Being the largest Red Diamonds in the world, The Moussaieff Red weighs 5.11 ct. It demonstrates an unusual trilliant cut and is internally flawless. 

In a rough state it had 13.9 ct, and was discovered in Brazil in the beginning of the 20th century. Initially it was named the Red Shield, but when  the Moussaieff jewelry firm acquired it, the stone was renamed. 

Today this stone is set in a ring with a price tag of $15 million.

Blue Diamonds

Meet the second rarest diamonds on the market. The chance to find a Blue Diamond in a mine is about 1 to 10,000. The gems displaying clear vivid blue color are even rarer. Real natural treasures! 

The Wittelsbach-Graff diamond 

Today, the Wittelsbach-Graff diamond weighs 31.06 ct and demonstrates the Fancy Deep Blue color. However, it wasn’t always like that.

According to the legend, this stone was acquired in 1664 by King Philip IV of Spain as a gift to his daughter Margarita Teresa. After her marriage, the stone became a part of the Austrian and Bavarian crown jewels.

In 1931 the Royal House of Wittelsbach offered the diamond for sale on Christie’s. However, it failed to reach the reserve price. In 2008 it was acquired by Laurence Graff for $23.4 million. 

Some time later Graff decided to recut the stone and plunged the public into shock. Because of cutting, the stone lost around 5 ct. However, its color shade and clarity grade improved greatly. Later Graff sold the stone for at least $80 million.

Green Diamonds

Fancy Green Diamonds are also included in a list of the rarest stones. Natural gems with a predominant green color are so rare that only few people have seen them live – and even then, most likely, at exhibitions or in museums.

The Dresden Green

The Dresden Green is the world’s largest Green Diamond. It weighs mind-blowing 40.70 ct, demonstrates perfect color distribution throughout the whole gem and possesses VS1 clarity. It is a treasure of an exceptional quality. 

Pink Diamonds

These delicate and romantic stones also break records of rarity and uniqueness. According to the statistics, out of the 20 million carats of diamonds mined each year, only 0,1% are pink. Although their faint pink shades are more available, their fancy intense pinks are extremely rare. Most Pink Diamonds come from the Argyle Mine in Australia. 

The CTF Pink Star

Today the CTF Pink Star holds several records such as being the biggest pink fancy vivid diamond ever discovered (it weighs mind-blowing 59.6 ct), the most valuable pink diamond in the world and the most expensive colored diamond ever sold at an auction – it was sold for $71.2 million.

Initially this stone was cut from 132.5 ct rough diamond mined in South Africa in 1999. 

In 2017 the Pink Star was sold for $71.2 million to renowned Hong Kong Jewelry Retailer, Chow Tai Fook, who renamed it as the CTF Pink Star. 

The rarest diamonds by type

Diamond types are a professional and scientific way to classify diamonds, based on their origin, physical and chemical characteristics and color. 

Type IIa

This type of diamond is considered to be the rarest one, comprising only 1% of all diamonds in the world. They are the most valued and the purest diamonds. 

Such stones are sometimes called Golconda Diamonds. It is connected to the fact that the famous Golconda mine in India produced most of history-making type IIa stones. 

Type IIa diamonds have no nitrogen or boron impurities, being the most chemically pure gems. As a result, most IIa diamonds are colorless or near colorless. However, they also exist in brown, purple, blue, or pink shades. These diamonds are the most expensive ones. 

Famous type IIa diamonds

  • The Taylor-Burton diamond
Frame 18

Perhaps the most famous diamond in the world, the Taylor Burton diamond is considered to be type IIa. 

Its rough version was discovered in the Premier Diamond mine in 1966. At that time it was a stone of impressive 241 ct. Later, Harry Winston cut this diamond into a 69.42 ct pear-shaped gem. 

In 1969 the stone was put up for auction. Richard Burton – Elizabeth Taylor’s husband – had set his maximum bid at $1 million, and had his lawyer, Aaron Frosch, bidding via telephone from London. To maximize his chances, Burton had Al Yugler of Frank Pollock and Sons jewelry bidding in the auction room. 

However, all his efforts were in vain. Robert Kenmore of Kenmore Corporation – the parent company of Cartier –  won the auction.

However, Cartier jewelers did not own the diamond too long – the day after the auction they got to sell it to Richard Burton and Elizabeth Taylor for 1.1 million dollars. At that time it was named The Cartier-Burton Diamond, but soon gained fame as the Taylor Burton Diamond. 


  • The Koh-i-noor
Frame 19

Being a part of the British Crown Jewels, the Koh-i-noor diamond – weighing 105.6 ct – is another example of the type IIa diamonds. 

It was found thousands of years ago, owned by numerous rulers over the years and all too often many of them lost their empires as well as their lives. It was never bought or sold but changed hands only due to inheritance, extortion, looting and trickery and, sometimes, gifting. 

Eventually, the Koh-i-Noor Diamond arrived in Britain. It was set into the crown of England’s Queen Mary in 1911 and then the crown of the Queen Mother in 1937 for her coronation. Since most people believe that the curse of the Diamond befalls only men, and not women, thereafter it was only worn by women.

Type Ib 

Type Ib is one of the rarest diamonds found on earth. Less than 0.1% natural diamonds are considered to fall into this category. These diamonds are usually saturated and intensely colored and include yellow, brown, and orange stones. Diamonds of this type are often classified as “canary” colored gems. These warm toned natural wonders are extremely rare.

Famous Type Ib diamond

Frame 25
  • The Pumpkin diamond

The Pumpkin diamond is a 5.54 ct stone of an unusual and notably intense color – Fancy Vivid Orange. It is also one of the largest Fancy Vivid Oranges. 

The Pumpkin diamond was mined in Central African Republic in 1997. Being cut and polished a little bit later, it was put to auction at Sotheby’s where it was bought by Ronald Winston of the House of Harry Winston for $1.3 million. It is currently estimated at $3 million.

Having got the Pumpkin diamond, Winston set it into a ring between two smaller white diamonds. Halle Berry wore this jewel to the 2002 Oscars where she won the Academy Award for Best Actress for her role in Monster’s Ball.

Type IIb

As for the IIb diamonds, they are also rare and usually have a bluish shade. Many gray-bluish diamonds are of this type. It is connected to the significant amounts of boron or nitrogen impurities in the stones of this category. 

Only 0.1% of all natural diamonds in the world are type IIb.  

Famous Type IIb diamonds

  • The Hope diamond
Frame 23

The Hope diamond of exceptional 45.52 ct is considered to be the most famous diamond in the world. Its color was described as “fancy dark grayish-blue”, “dark blue in color” and “steely-blue”.

This stone was found in India in the 17th century. Being notorious for bringing bad luck to its owners, it has a dark and – as legends say – cursed history. 

  • The Idol’s Eye
Image asset

This sparkling stone first appeared in 1865 – and was immediately offered at Christie’s in London. It was bought by the Ottoman sultans.

All we know about this diamond is that it was found in India, it is incredibly beautiful, and it was cut to a size of 70 ct. One day, a famous American jeweler Harry Winston got the stone and sold it to an American gem collector called May Bonfils Stanton. After her death, the stone was sold again to a private collector.

Subscribe to discover the world of diamonds and gems. If you have any questions, please let us know

Other news

View all

Bonhams Fancy and Brilliant online auction features 23 beautiful lots each of which is unique and special in its own way. We invite…

June 08, 2024

A 53.04-carat D-color, internally perfect diamond is expected to fetch up to $5 million at the June 7 Sotheby’s Magnificent Jewels sale in…

June 06, 2024

We’ve got some new spinels! We now have two more stones in our collection. Our spinel boasts vibrant colors, mesmerizing brilliance, and a…

June 05, 2024